Answer: 26
Step-by-step explanation: Tom would have 26 marbles according to my work On my paper.
Luke has X marbles.
Tom has twice as many so he has 2x marbles.
Together they have 39:
X + 2x = 39
Simplify:
3x = 39
Divide both sides by 3:
x = 39 / 3 = 13
Tom has 2(13) = 26 marbles.